of determining whether any affection produced in us
is produced by ourselves rather than by the thing in itself;
consequently we could never say that a given affection was an
appearance due to _ourselves_, and therefore to _inner_ sense. On the
contrary, we should ascribe all affections to things in themselves,
and should, therefore, be unable to recognize an _inner_ sense at all.
In order to recognize an inner sense we must know that certain
affections are due to _our_ activity, and, to do this, we must know
what the activity consists in--for we can only be aware that we are
active by being aware of an activity of ours of a particular
kind--and, therefore, we must know ourselves. Unless, then, we know
ourselves, we cannot call any affections internal.

If, however, the doctrine of an internal sense is obviously untenable
from Kant's own point of view, why does he hold it? The answer is
that, inconsistently with his general view, he continues to think of
the facts as they really are, and that he is deceived by an ambiguity
into thinking that the facts justify a distinction between internal
and external sense.

He brings forward only one argument to show that time is the form of
the internal sense. "Time is nothing else than the form of the
internal sense, i. e. of the perception of ourselves and our inner
state. For time cannot be any determination of external phenomena; it
has to do neither with a shape nor a position; on the contrary, it
determines the relation of representations in our internal state."[9]

[9] B. 49 (b), M. 30 (b).

To follow this argument it is first necessary to realize a certain
looseness and confusion in the expression of it. The term 'external',
applied to phenomena, has a double meaning. It must mean (1) that of
which the parts are external to one another, i. e. spatial; for the
ground on which time is denied to be a determination of external
phenomena is that it has nothing to do with a shape or a position. It
must also mean (2) external to, in the sense of independent of, the
mind; for it is contrasted with our internal state, and if 'internal',
applied to 'our state', is not to be wholly otiose, it can only serve
to emphasize the contrast between our state and something external to
in the sense of independent of us. Again, 'phenomena,' in the phrase
'external phenomena', can only be an unfortunate expression for
things independent of the mind, these things being here called
phenome